The runner had just passed the same area along the Santa Fe Trail on the East side of Fountain Creek about 30 minutes earlier at 10:30 a.m. and hadn’t seen the dead man.

Several other people using the trail soon gathered near the body. Colorado Springs police were called.

The dead man had long shaggy, graying hair. He had been stabbed several times.

The amount of bleeding at the location where he was found suggested it was the same spot where he had been attacked, just south of Cimmaron Bridge.

A perimeter was set up. The El Paso County coroner’s office was called and the crime scene was searched.

The bearded dead man was a well-known transient, whose campsite was about three-quarters of a mile away.

John Vincent Knudsen was described by family as somewhat of a gypsy.

After his birth in Fort Ord, Calif., in 1956 Knudsen traveled through Europe and the United States as his father was frequently transferred to new U.S. Army assignments.

“These years of traveling, seeing new places, meeting new people and experiencing new things continued to influence John throughout the remainder of his life,” family members would write in an obituary.

He had gone throughout the country as a long-haul driver. He once worked in construction.

“John’s love for his dogs is legendary,” the obituary says.

Everywhere he went he was flanked by Reuben, Rusty or Booger Ray, his canine friends.

By the day he was kidnapped and murdered, Thomas Ray Carpenter had been a Colorado state trooper for five years. The 31-year-old man had become a trooper in 1968 after serving three years in the U.S. Marine Corps. He was a highly regarded and decorated trooper.

Trooper Thomas Carpenter, 31

Carpenter was married to Phyllis and the couple had three young children, ages 9, 7, and 4. They lived in Lafayette. He was a quiet, religious man who didn’t drink alcohol. He wanted to make a career of being a CSP trooper.

Carpenter was assigned to the Colorado State Patrol’s Broomfield district that Thursday, Dec. 27, 1973. He worked the Interstate 25 corridor.

9:58 a.m.

He drove to the side of U.S. 36 near Broadway that morning. A car was pulled off on the shoulder of the highway. Carpenter was either intending to see if he could help a stranded motorist or he had seen something that appeared to be suspicious.

He did not make a radio report that he had pulled over at the time. Witnesses would later tell police that they saw Carpenter driving a patrol car with two men in the back seat at about the same time.

That morning at 9:58 a.m., Carpenter received a call from a dispatcher to go to an accident at East 58th Avenue and I-25. He told the dispatcher that he was at Interstate 70 and Havana at the time.

That was somewhat odd. He was about eight miles east from the area he was supposed to patrol.

10:04 a.m.

A dispatcher called again six minutes after the first call to ask Carpenter if he was going to the accident.

By 1968, when Richard Nixon won his first term as president, Grey was the steel company’s general manager of purchasing. In February of that year The Denver Post ran his picture on the business page after he had been appointed vice president of sales for CF&I Steel Corp. based in Denver.

He moved into a luxury home at 3 Sedgwick Drive in Cherry Hills Village, where he lived with his wife and the youngest of his four children, 17-year-old Kathy.

On Oct. 31, 1968, Nixon enjoyed an advantage over Democrat Hubert Humphrey according to the polls in the last week of the election campaign, Grey returned home early from a business trip to spend time with his family in Colorado, and Kathy was answering the door bell for trick-or-treaters.

It was their first Halloween in Colorado.

8:30 p.m.

At around 8:30 p.m. that night, the door bell rang.

Kathy “assumed she would be greeting the usual costumed trick-or-treaters,” an Arapahoe County Sheriff’s Department report says. “Instead she opened the door to a nightmare that would change their lives forever.”

When Kathy opened the door two men shoved their way into the home, then-Sheriff Roy Vogt told former Denver Post staff writer Bernard Beckwith.

Janyce “Janny” Hansen was a glamorous, beautiful former model who died mysteriously in Aurora, Colorado 30 years ago.

Even in death, the black high heel shoe on the cement garage floor next to the convertible Mercedes Benz was a cinematic touch that reflected her glitzy life on runways and at high-brow social gatherings among Denver’s wealthy and elite.

Her second husband, Richard Hansen, 12 years her elder, was a prosperous builder. The couple raised a family in an upscale Aurora neighborhood while Richard Hansen went from one lucrative housing or retail construction project to the next.

The story of the model turned domestic socialite was an illusion.

The couple lived a decadent lifestyle. There had been costume parties in which women wore scanty clothing and even talk about wife swapping.

Like many evenings for the family, the Hansens had gone out for dinner on Thursday evening, Sept. 20, 1984, to the El Torito Lounge on East Hampden Avenue in Denver. But they didn’t eat anything. They were drinking margaritas all night.

They were talking about a trailer park they had recently purchased. He was wearing a tan sport jacket. She was wearing a lavender dress with a necklace with black beads.

But when they returned home he realized that he had left his tan suit coat at the restaurant, so he drove back to the restaurant to retrieve it and was later supposed to meet his wife at another lounge, the story went.

The FBI collected scrapings from under her fingernails after the 16-year-old’s body was found in her sleeping bag on Aug. 18, 1963, at a girls’ camp in the Pike National Forest.

That evidence, collected 50 years ago, could lead to her killer, according to cold-case investigator Cheryl Moore of the Jefferson County Sheriff’s Office.

Moore has submitted the DNA evidence for processing, she said.

That Saturday night in 1963, her tent companion, Claudia Stride, had gone to the infirmary, and Beck spent the night alone. The nearest tent was 75 feet away, and nobody reported hearing anything during the night.

According to Denver Post news reports at the time, someone sexually assaulted Beck and strangled her to death.

The Jefferson County Sheriff’s Office was not notified until eight hours after her body was discovered and valuable evidence was likely lost at the crime scene, then-Sheriff Harold Bray said at the time. Before authorities were called, camp officials thoroughly cleaned the tent, and her tent companion took all her belongings home.

At first, camp officials believed she died of natural causes. But then-Coroner Ken Raynie found finger marks on her neck and signs that she had been sexually assaulted.

Investigators interviewed 105 campers, program aides and officials. No one was ever charged in the murder.

If you have information about this case: Contact cold-case investigator Cheryl Moore of the Jefferson County Sheriff’s Office at 303-271-5625 or cmoore@jeffco.com.

The early-morning confrontation led into the parking lot of the Brunswick Zone blowing alley at 999 N. Circle Drive. where it became a full-fledged melee. The fist-fight turned into a knife and gun fight.

The combatants jumped in at least four different cars and a chase ensued that quickly turned into a running gun battle along a normally quiet residential neighborhood of small homes.

As usual I was working the Saturday morning crime shift that July 9, 2011 at The Denver Post. I drove to Colorado Springs.

At the corner of Mission and Tia Juana streets, about a block from the bowling alley, tire treads crisscrossed pools of blood.

I walked down an alley behind a row of homes just off of Tia Juana Street. It wasn’t difficult to find people willing to describe what happened. People were in their back yards talking to neighbors about what had taken place the night before.

It was tough to get anyone to give their names for the article, though. They were afraid that the people capable of the extreme violence they had witnessed could come back and attack them.

Many were asleep when they heard what sounded like a drag race on their street, punctuated by the sounds of gunshots and frantic screaming and taunts.

“Shoot him! Shoot him!” Doug heard a man yell near the south end of the 800 block of Tia Juana. Cars were screeching and crashing.

In apparent answer to the call came a succession of loud pops, said Doug, a Navy veteran. He heard at least two different calibers of guns being fired.

“I heard some cars squealing,” Larry, who lives on the street, told me. “Then I heard what I thought were fireworks. Pow, pow, pow, pow. Bullets were flying everywhere. I heard screaming.”

About 100 feet north on Tia Juana, Leticia, who asked that her last name not be used, said she saw a bald man slam on the brakes in the street in front of her house, get out of a blue car, fire a gun several times straight up into the air and curse loudly.

” ‘Now come on (expletives),’ he yelled,” Leticia said. She also saw two other bald men fist fighting farther up the street.

Her neighbor June said she heard what sounded like a car crash.

She dashed to her window and lifted the blinds just in time to see a young man about 18 years old jump out of a white Dodge Neon at the corner of Tia Juana and Mission and flee from several cars that had boxed his car in.

Donald Allison was an accomplished biologist and oceanographer. His studies and reports were published in scientific journals and helped doom DDT spraying.

Donald had a wanderlust that tempted him to sail around the world. He wasn’t so naive, though, that he didn’t carry a rifle on the open sea during many voyages. He was sort of an Indiana Jones with a preference for environmental rather than archaeological treasures.

He was also loved traipsing across the continent, mostly to remote areas. His dream was to build a cabin in the wilderness and once bought 200 acres of forested land in Minnesota. His mode of travel was a faded blue Volkswagen camper bus, which held most of his possessions.

While on one of those trips, which led him through Aspen, someone shot Donald in the chest, stole his bus and, with it, most his identification.

Donald’s body was found near an isolated village near Aspen in 1978. But no one knew who the itinerant scientist was.

His name would remain a mystery for decades.

Robin Allison, his daughter, went to college, married, moved from place to place 30 years without knowing what had become of her father. He had been so many things during his lifetime that it was difficult to guess what had become of him.

At different times in his life, Allison had been a surveyor, fisheries biologist, Environmental Protection Agency agent, miner, park ranger and oceanographer.

Although he was born in Toronto, Canada, Allison had dual Canadian and U.S. citizenship. He attended Pickering Prep School in Toronto before enrolling in the University of Toronto.

He registered for the U.S. military draft in 1950. While waiting to be drafted he worked as a miner just outside of Leadville for a season and then near Salt Lake City for another.

In 1951, Allison was drafted in the U.S. Army and became a paratrooper. He earned an Army commendation ribbon and medal after organizing food, medicine and supply drops in Holland following the February 1953 flood disaster.

He moved to Moscow, Idaho to attend the University of Idaho. He got married in Idaho in 1955 and the couple had three children. Donald graduated with a bachelor’s degree in forestry with a fisheries management option.

In a ravine in Geer Canyon, they found the partially buried remains of a skeleton.

It’s likely that when the body of a woman or girl was originally buried it was completely underground.

But unless animal remains are buried deep enough, scavengers will dig them up, feed on the remains and spread the bones.

In this case, Boulder County Sheriff’s investigators had a good idea whose remains were in the shallow grave.

Fourteen-year-old Longmont Junior High School student Margaret “Margo” Henriette Hillman had disappeared from an old-fashioned, cowboy-style party in a large barn at the 5,000-acre Heil Valley ranch north of Lefthand Canyon nearly a year earlier.

The last anyone had seen Margo was shortly before midnight on Sept. 24, 1983. She told her parents that a cousin had offered to give her a ride home.

Three of Margo’s cousins were supposed to take her home at 1:30 a.m. on Sept. 25. But when it came time to go home they couldn’t find Margo and believed she had found another way to get home.

They drove home without her. The next morning, their mother asked where Margo was. But the cousins didn’t know.

A search began immediately.

Family members returned to the barn, and searched the large wooded territory around it.

Kirk Mitchell is a general assignment reporter at The Denver Post who focuses on criminal justice stories. He began working at the newspaper in 1998, after writing for newspapers in Mesa, Ariz., and Twin Falls, Idaho, and The Associated Press in Salt Lake City. Mitchell first started writing the Cold Case blog in Fall 2007, in part because Colorado has more than 1,400 unsolved homicides.